1. Field of the Invention
The present invention generally relates to fiber optics devices and, more particularly, to fiber optics tactile sensors,
2. Description of the Prior Art
Quite often it is desirable or necessary to sense the contact between objects. For example when operating a mechanical hand it is often important to determine when the hand grips or contacts a target object. The force with which the hand grips the object is also of importance in certain cases.
Visual techniques alone are inadequate to provide such information. Quite often the hand itself blocks any visual path, even for television cameras. Electrical tactile sensors on the hand are also unsatisfactory since they are subject to induced spurious signals, especially when long leads are required from the hand to the operator's location. Strong magnetic fields, which may be present, induce noise and spurious signals. Also, long parallel sensor leads induce crosstalk between channels. The motion of the hand itself induces noise. All these factors tend to obscure small sensor signals, which are present at the time of initial contact, when the forces between the hand and the object are very small. Various techniques have been attempted to overcome these problems. They have been found to be costly, bulky and of limited reliability. Similar problems exist when a tactile sensor which has to be used with other than mechanical hands is remotely located from the operator's or signal processing location. A need therefore exists for a new tactile sensor, which will greatly reduce, if not completely eliminate, the above-discussed disadvantages of prior art sensors.